1. Field of the Invention
The present invention is related to a bearing with auxiliary magnetism and particularly to bearing assembly, which provides at least a magnetic part in a shaft seat of the motor to attract the shaft, for the shaft running steadily.
2. Brief Description of the Related Art
Due to information industry progressing rapidly, operation speed of the central processing unit in the information products is getting faster and generated heat is increased along with the faster operation speed. In order to remove the heat, a heat dissipation device is essential for the information products. The most popularly used heat dissipation device is the cooling fan because the cooling fan is very convenient to be used and the cost of the cooling fan is cheap too. Quality of the cooling fan totally depends on if the motor is in a state of running smoothly. Unsteady running motor significantly affects normal operation of the entire system or device and the bearing in the motor is a key factor to influence running quality and running steadiness of the motor.
Generally, a bearing used in the motor usually has a plurality of balls and the balls rotate in the bearing casing. The bearing casing is easy to deviate from the original position thereof due to the inclining shaft so that a clearance is created in the bearing casing to affect running and performance of the motor. Thus, disadvantages such as vibration, noise, generating heat and undesirable power consumption occur in the motor.
Taiwanese Patent Official gazette No. 535,885 discloses a cooling fan, which is composed of a fan blade set, a coil set, a circuit board and a bottom plate. The fan blade set has a shaft inserted into the coil set and there are a ball bearing and an oily bearing stacked vertically in the coil set with O rings and C shaped retaining rings at upper sides and the lower sides of the bearings fixedly attached to the shaft. The characteristics of the prior art is in that a magnetic device is provided on the bottom plate corresponding to the lower end of the shaft and the magnetic device can attract the shaft to keep the fan blades at a fixed position. In this way, a preset pressure can be created to exert the ball bearing such that the ball in the bearing can run at the same track. Besides, noise resulting from friction can be removed because of the magnetic device attracting the shaft.
However, the preceding magnetic device provides a flat shape and only the lower end of the shaft can be attracted. In this way, it is obvious that the shaft is unable to avoid disadvantages such as swaying and noising.